I got both, who ever replaced it before me didnt use one so im gona use both. One more question, when bleeding the system, do i open the bleeder screw when the car is warmed up or when i first start it?

What I usually do is,
leave the rad cap off,
open bleeder
start engine,
carefully reach down to lower radiator hose and repetitively squeeze the lower hose while keeping an eye on the coolant level in the radiator. Top off as the engine gets warm and as the level goes lower. Watch the bleed valve also.

ok, my lower radiator hose is hard. Real hard, i can not squeeze it at all. What could have caused this, stop leak? I am on my way to get a new hose but what in the world would make it hard. Its like there is something in it. By the way i didnt put stop leak in but someone before me could have.

ok after some research, the hose being hard is normal, but i have a new problem. I bleed the system but still no heat and now its misfiring very bad. I cant drive down the street its misfiring so bad. It had a misfire before but was never this bad. Could i have not but the gaskets in place just right? or could something have fell into the engine when the intake was off. i hear a ping sound in the exhaust everynow and again. I new it would be a lil rough running being a old car that sat for 3 days but this is something more.

its running smooth again the 3 and 5 wires got switched, but i still have no heat. i bleed it again but it still got no heat. its like its in between cold and hot. new thermostat 195 temp and new anti freeze. anything else can keep the heat from working? first it was hotter on pass side than driver then no heat at all.